Thing 59: A Cool Feature of Haft Schroedinger Chess

The Antumbra Station write-up on Haft Schroedinger Chess says that one of the consequences of the rules is that

You can't capture the Queen unless you capture a piece that is currently locked in as the Queen.

I demonstrate in this post that that claim is false!

The following position came up when I was playing Haft Chess, and I noticed an interesting phenomenon.

In this position, if black moves their queenrook to c3, then white has the option to move their kingrook to b2 thereby forcing it to be a king, and since if the black queenrook were a queen, white's move would have been illegal, black's queenrook must collapse to just a rook.

Similarly, when a pawn promotes (to an indeterminate piece), a similar maneuver can be used by the other player to move their king into a square a rook's move away from the promoted pawn, thereby reducing the promoted piece to a mere bishop or knight.